Salt in stone

This is sent on behalf of colleagues in Tallinn, Estonia. It is
intended that a number of stone-built medieval cellars in Tallinn be
refurbished for other uses. These cellars have been used as salt
stores, sometimes for centuries. However the local limestone and
lime mortar used in their construction were not of the greatest
quality and the salt has penetrated the walls to a depth of 20
centimetres. They are interested in knowing whether there is any
sensible way of extracting the salt; at first sight stripping out
the walls and refacing them with new stone seems the most effective
way but they would like to retain the medieval stonework where
possible.

Peter Northover
Materials Science-based Archaeology Group,
Department of Materials,
University of Oxford

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                  Conservation DistList Instance 12:3
                  Distributed: Tuesday, June 16, 1998
                        Message Id: cdl-12-3-007
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